US Patent 7173908 Flexible policing technique for telecommunications traffic

A policing technique for a telecommunications traffic of variable length packets is described. The technique uses a plurality of police engines, grouped in pairs. A selection module selects a police engine pair to process a packet. Each police engine contains a conformance unit, credit unit and a debit unit, in which the credit update of one police engine influences the credit update of the other police engine in the pair. The technique also uses a combinatorial function to decide on a category of a processed packet and which police engines to update their debit units.